It is very important — and often very difficult! — to follow the naming conventions that have been established by the community. The hierarchy is constantly growing and being improved-upon. If you're at all uncertain how to name a new category use the "Request a New Category" form or ask in G2G using the tag categorization. If you want to help us create and maintain the category hierarchy, please join our Categorization Project.

General Rules

Do not use special characters such as !, @, #, $, %, ^, &, *,"", / and |. The only allowed characters are Letters in any alphabet, numbers, space, comma, dot, hyphen (only the normal one but not wide, ...), single quotation mark (as apostrophe but do not use apostrophe) and parentheses (in pair). There is also a colon in the name but must be used only following "Category:". Quotation marks and & are often used for names in Wikipedia and at Find A Grave, neither can be used on Wikitree. Spaces may be used (they become underscores when saved). Non-Latin alphabets are fine but still stick to characters and numbers.In short: Please use only spaces, commas, regular hyphens, and parentheses as characters in category names.

We use singular form for topic categories and plural form for set categories.

Topic categories are named after a topic, for example, Category:Norfolk contains subcategories, free-space pages and profiles (when no lower category is known) relating to the topic Norfolk.

Set categories are named after the set of profiles they contain, so use the plural form if there is one. For example, we use Category:Czech Artists not Category:Czech Artist. This doesn't mean that we add unnecessary words to the name in order to pluralize it, e.g. we say Category:Baseball instead of Category:Baseball Topics.

Do not begin category names with The. There are some exceptions to this rule, for instance there is a place called The Gap in New South Wales.

If a category could contain millions of people create a narrower subcategory. Ideally, bottom-level categories should be much smaller, with no more than a few thousand people in them. This isn't always possible, e.g. with towns and cities, but we should aim to create narrow categories when we can.

If a category could only contain a few people do not create it. Use the category above it instead. For example, the Soyuz programme by the Soviet Union launched a series of crewed (manned) spaceflights that only carried a maximum of three crew members. In this case, we would not create a category for each spaceflight to only hold a maximum of three profiles, but would rather use the higher level category for Category:Soyuz Cosmonauts.

If a mid-level category would be empty and only have one subcategory do not create it. We don't want to create extra layers of navigation. This rule explains why some bottom-level categories have names like "X Group Members" while most just say have "X Group." For example, we never say "X Location Residents" or "X Cemetery Burials." We do put professional baseball players in Category:Professional Baseball Players rather than Category:Professional Baseball because Category:Professional Baseball can contain many other subcategories. (If players were going in Category:New York Yankees we probably would not need Category:New York Yankees Players because Category:New York Yankees would not have a lot of subcategories.)

A fundamental style rule on WikiTree is to "use their conventions instead of ours," i.e. we should attempt to use the name that the person themselves would have known and used. For regional categorization, for example, this means using the place name in the language and time in which the person lived rather than what it's called now in English.

This applies for bottom-level categories that contain profiles but may not apply to higher-level categories. Higher-level categories exist for our own organizational and navigational purposes, e.g. a town that no longer exists may be included in its current county (? example?).

In some cases this may not be practical. The purpose of categorization is to group profiles. If the people we're trying to group would have used different names for the same thing it may make sense. However, keep in mind that this can often be achieved through mid-level categories. For example, we could have "Czech Bricklayers" with whatever "bricklayers" is in Czech, as a subcategory of Bricklayers.

When sections here get too large they can be split off into subsidiary pages. They should be named using this style: Category Names for European Aristocrats, Category Names for Regions, etc. These should be categorized under Category:Categorization Help, project categories if appropriate, etc.

Category Names for DNA Projects

Category Names for Maintenance Categories

Maintenance categories should be linked to a project, generally, with a few exceptions. They should lead with the project name, followed by a "needs" statement, like "needs PPP". These should be discussed if there isn't an existing parameter so a standard can be added, as they are linked from project box templates. For example, [[Category:Quakers Project Needs Biography]]. A few maintenance categories will not fit the "needs" format, namely Unsourced and Unconnected profiles.

Category Names for Military Topics

Guidelines will be published after collaboration with the WikiTree community.

Category Names for One Name Studies

Category Names for Personal Categories

A personal category is a category that is named with your WikiTree ID.

Each WikiTree ID is unique so when you make a category named with your ID you are making a unique category that will be there exclusively for your use. You can add subcategories to it or you can just use it alone to hold notes and profiles on which you need to do additional work.
See Personal Categories for more information.

Category Names for Regions

Cities, countries and other locations are organized in a category hierarchy. The top level is the Category:Regions. It contains all the continents which are then divided in countries, states or other sub-regions.

Category names for locations follow the same general principles as Location Fields. Categories for modern countries use the short form in common usage, as in Category:Australia not Category:Commonwealth of Australia.

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